mariadb/storage/innobase/include/page0cur.h
Marko Mäkelä 24fe53477c MDEV-29603 btr_cur_open_at_index_side() is missing some consistency checks
btr_cur_t: Zero-initialize all fields in the default constructor.

btr_cur_t::index: Remove; it duplicated page_cur.index.

Many functions: Remove arguments that were duplicating
page_cur_t::index and page_cur_t::block.

page_cur_open_level(), btr_pcur_open_level(): Replaces
btr_cur_open_at_index_side() for dict_stats_analyze_index().
At the end, release all latches except the dict_index_t::lock
and the buf_page_t::lock on the requested page.

dict_stats_analyze_index(): Rely on mtr_t::rollback_to_savepoint()
to release all uninteresting page latches.

btr_search_guess_on_hash(): Simplify the logic, and invoke
mtr_t::rollback_to_savepoint().

We will use plain C++ std::vector<mtr_memo_slot_t> for mtr_t::m_memo.
In this way, we can avoid setting mtr_memo_slot_t::object to nullptr
and instead just remove garbage from m_memo.

mtr_t::rollback_to_savepoint(): Shrink the vector. We will be needing this
in dict_stats_analyze_index(), where we will release page latches and
only retain the index->lock in mtr_t::m_memo.

mtr_t::release_last_page(): Release the last acquired page latch.
Replaces btr_leaf_page_release().

mtr_t::release(const buf_block_t&): Release a single page latch.
Used in btr_pcur_move_backward_from_page().

mtr_t::memo_release(): Replaced with mtr_t::release().

mtr_t::upgrade_buffer_fix(): Acquire a latch for a buffer-fixed page.
This replaces the double bookkeeping in btr_cur_t::open_leaf().

Reviewed by: Vladislav Lesin
2022-11-17 08:19:01 +02:00

303 lines
12 KiB
C

/*****************************************************************************
Copyright (c) 1994, 2016, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2018, 2022, MariaDB Corporation.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
*****************************************************************************/
/********************************************************************//**
@file include/page0cur.h
The page cursor
Created 10/4/1994 Heikki Tuuri
*************************************************************************/
#ifndef page0cur_h
#define page0cur_h
#include "page0page.h"
#ifdef UNIV_DEBUG
/*********************************************************//**
Gets pointer to the page frame where the cursor is positioned.
@return page */
UNIV_INLINE
page_t*
page_cur_get_page(
/*==============*/
page_cur_t* cur); /*!< in: page cursor */
/*********************************************************//**
Gets pointer to the buffer block where the cursor is positioned.
@return page */
UNIV_INLINE
buf_block_t*
page_cur_get_block(
/*===============*/
page_cur_t* cur); /*!< in: page cursor */
/*********************************************************//**
Gets pointer to the page frame where the cursor is positioned.
@return page */
UNIV_INLINE
page_zip_des_t*
page_cur_get_page_zip(
/*==================*/
page_cur_t* cur); /*!< in: page cursor */
/* Gets the record where the cursor is positioned.
@param cur page cursor
@return record */
UNIV_INLINE
rec_t *page_cur_get_rec(const page_cur_t *cur);
#else /* UNIV_DEBUG */
# define page_cur_get_page(cur) page_align((cur)->rec)
# define page_cur_get_block(cur) (cur)->block
# define page_cur_get_page_zip(cur) buf_block_get_page_zip((cur)->block)
# define page_cur_get_rec(cur) (cur)->rec
#endif /* UNIV_DEBUG */
# define is_page_cur_get_page_zip(cur) is_buf_block_get_page_zip((cur)->block)
/*********************************************************//**
Sets the cursor object to point before the first user record
on the page. */
UNIV_INLINE
void
page_cur_set_before_first(
/*======================*/
const buf_block_t* block, /*!< in: index page */
page_cur_t* cur); /*!< in: cursor */
/*********************************************************//**
Sets the cursor object to point after the last user record on
the page. */
UNIV_INLINE
void
page_cur_set_after_last(
/*====================*/
const buf_block_t* block, /*!< in: index page */
page_cur_t* cur); /*!< in: cursor */
/*********************************************************//**
Returns TRUE if the cursor is before first user record on page.
@return TRUE if at start */
UNIV_INLINE
ibool
page_cur_is_before_first(
/*=====================*/
const page_cur_t* cur); /*!< in: cursor */
/*********************************************************//**
Returns TRUE if the cursor is after last user record.
@return TRUE if at end */
UNIV_INLINE
ibool
page_cur_is_after_last(
/*===================*/
const page_cur_t* cur); /*!< in: cursor */
/**********************************************************//**
Positions the cursor on the given record. */
UNIV_INLINE
void
page_cur_position(
/*==============*/
const rec_t* rec, /*!< in: record on a page */
const buf_block_t* block, /*!< in: buffer block containing
the record */
page_cur_t* cur); /*!< out: page cursor */
/***********************************************************//**
Inserts a record next to page cursor. Returns pointer to inserted record if
succeed, i.e., enough space available, NULL otherwise. The cursor stays at
the same logical position, but the physical position may change if it is
pointing to a compressed page that was reorganized.
IMPORTANT: The caller will have to update IBUF_BITMAP_FREE
if this is a compressed leaf page in a secondary index.
This has to be done either within the same mini-transaction,
or by invoking ibuf_reset_free_bits() before mtr_commit().
@return pointer to record if succeed, NULL otherwise */
UNIV_INLINE
rec_t*
page_cur_tuple_insert(
/*==================*/
page_cur_t* cursor, /*!< in/out: a page cursor */
const dtuple_t* tuple, /*!< in: pointer to a data tuple */
rec_offs** offsets,/*!< out: offsets on *rec */
mem_heap_t** heap, /*!< in/out: pointer to memory heap, or NULL */
ulint n_ext, /*!< in: number of externally stored columns */
mtr_t* mtr) /*!< in/out: mini-transaction */
MY_ATTRIBUTE((nonnull, warn_unused_result));
/***********************************************************//**
Inserts a record next to page cursor on an uncompressed page.
@return pointer to record
@retval nullptr if not enough space was available */
rec_t*
page_cur_insert_rec_low(
/*====================*/
const page_cur_t*cur, /*!< in: page cursor */
const rec_t* rec, /*!< in: record to insert after cur */
rec_offs* offsets,/*!< in/out: rec_get_offsets(rec, index) */
mtr_t* mtr) /*!< in/out: mini-transaction */
MY_ATTRIBUTE((nonnull, warn_unused_result));
/***********************************************************//**
Inserts a record next to page cursor on a compressed and uncompressed
page.
IMPORTANT: The caller will have to update IBUF_BITMAP_FREE
if this is a compressed leaf page in a secondary index.
This has to be done either within the same mini-transaction,
or by invoking ibuf_reset_free_bits() before mtr_commit().
@return pointer to inserted record
@return nullptr on failure */
rec_t*
page_cur_insert_rec_zip(
/*====================*/
page_cur_t* cursor, /*!< in/out: page cursor,
logical position unchanged */
const rec_t* rec, /*!< in: pointer to a physical record */
rec_offs* offsets,/*!< in/out: rec_get_offsets(rec, index) */
mtr_t* mtr) /*!< in/out: mini-transaction */
MY_ATTRIBUTE((nonnull, warn_unused_result));
/***********************************************************//**
Deletes a record at the page cursor. The cursor is moved to the
next record after the deleted one. */
void
page_cur_delete_rec(
/*================*/
page_cur_t* cursor, /*!< in/out: a page cursor */
const rec_offs* offsets,/*!< in: rec_get_offsets(
cursor->rec, index) */
mtr_t* mtr) /*!< in/out: mini-transaction */
MY_ATTRIBUTE((nonnull));
/** Apply a INSERT_HEAP_REDUNDANT or INSERT_REUSE_REDUNDANT record that was
written by page_cur_insert_rec_low() for a ROW_FORMAT=REDUNDANT page.
@param block B-tree or R-tree page in ROW_FORMAT=COMPACT or DYNAMIC
@param reuse false=allocate from PAGE_HEAP_TOP; true=reuse PAGE_FREE
@param prev byte offset of the predecessor, relative to PAGE_OLD_INFIMUM
@param enc_hdr encoded fixed-size header bits
@param hdr_c number of common record header bytes with prev
@param data_c number of common data bytes with prev
@param data literal header and data bytes
@param data_len length of the literal data, in bytes
@return whether the operation failed (inconcistency was noticed) */
bool page_apply_insert_redundant(const buf_block_t &block, bool reuse,
ulint prev, ulint enc_hdr,
size_t hdr_c, size_t data_c,
const void *data, size_t data_len);
/** Apply a INSERT_HEAP_DYNAMIC or INSERT_REUSE_DYNAMIC record that was
written by page_cur_insert_rec_low() for a ROW_FORMAT=COMPACT or DYNAMIC page.
@param block B-tree or R-tree page in ROW_FORMAT=COMPACT or DYNAMIC
@param reuse false=allocate from PAGE_HEAP_TOP; true=reuse PAGE_FREE
@param prev byte offset of the predecessor, relative to PAGE_NEW_INFIMUM
@param shift unless !reuse: number of bytes the PAGE_FREE is moving
@param enc_hdr_l number of copied record header bytes, plus record type bits
@param hdr_c number of common record header bytes with prev
@param data_c number of common data bytes with prev
@param data literal header and data bytes
@param data_len length of the literal data, in bytes
@return whether the operation failed (inconcistency was noticed) */
bool page_apply_insert_dynamic(const buf_block_t &block, bool reuse,
ulint prev, ulint shift, ulint enc_hdr_l,
size_t hdr_c, size_t data_c,
const void *data, size_t data_len);
/** Apply a DELETE_ROW_FORMAT_REDUNDANT record that was written by
page_cur_delete_rec() for a ROW_FORMAT=REDUNDANT page.
@param block B-tree or R-tree page in ROW_FORMAT=REDUNDANT
@param prev byte offset of the predecessor, relative to PAGE_OLD_INFIMUM
@return whether the operation failed (inconcistency was noticed) */
bool page_apply_delete_redundant(const buf_block_t &block, ulint prev);
/** Apply a DELETE_ROW_FORMAT_DYNAMIC record that was written by
page_cur_delete_rec() for a ROW_FORMAT=COMPACT or DYNAMIC page.
@param block B-tree or R-tree page in ROW_FORMAT=COMPACT or DYNAMIC
@param prev byte offset of the predecessor, relative to PAGE_NEW_INFIMUM
@param hdr_size record header size, excluding REC_N_NEW_EXTRA_BYTES
@param data_size data payload size, in bytes
@return whether the operation failed (inconcistency was noticed) */
bool page_apply_delete_dynamic(const buf_block_t &block, ulint prev,
size_t hdr_size, size_t data_size);
MY_ATTRIBUTE((warn_unused_result))
/****************************************************************//**
Searches the right position for a page cursor. */
bool
page_cur_search_with_match(
/*=======================*/
const dtuple_t* tuple, /*!< in: data tuple */
page_cur_mode_t mode, /*!< in: PAGE_CUR_L,
PAGE_CUR_LE, PAGE_CUR_G, or
PAGE_CUR_GE */
ulint* iup_matched_fields,
/*!< in/out: already matched
fields in upper limit record */
ulint* ilow_matched_fields,
/*!< in/out: already matched
fields in lower limit record */
page_cur_t* cursor, /*!< in/out: page cursor */
rtr_info_t* rtr_info);/*!< in/out: rtree search stack */
#ifdef BTR_CUR_HASH_ADAPT
MY_ATTRIBUTE((warn_unused_result))
/** Search the right position for a page cursor.
@param[in] tuple key to be searched for
@param[in] mode search mode
@param[in,out] iup_matched_fields already matched fields in the
upper limit record
@param[in,out] iup_matched_bytes already matched bytes in the
first partially matched field in the upper limit record
@param[in,out] ilow_matched_fields already matched fields in the
lower limit record
@param[in,out] ilow_matched_bytes already matched bytes in the
first partially matched field in the lower limit record
@param[in,out] cursor page cursor */
bool
page_cur_search_with_match_bytes(
const dtuple_t* tuple,
page_cur_mode_t mode,
ulint* iup_matched_fields,
ulint* iup_matched_bytes,
ulint* ilow_matched_fields,
ulint* ilow_matched_bytes,
page_cur_t* cursor);
#endif /* BTR_CUR_HASH_ADAPT */
/***********************************************************//**
Positions a page cursor on a randomly chosen user record on a page. If there
are no user records, sets the cursor on the infimum record. */
void page_cur_open_on_rnd_user_rec(page_cur_t *cursor);
/** Index page cursor */
struct page_cur_t{
dict_index_t* index;
rec_t* rec; /*!< pointer to a record on page */
rec_offs* offsets;
buf_block_t* block; /*!< pointer to the block containing rec */
};
MY_ATTRIBUTE((nonnull, warn_unused_result))
inline rec_t *page_cur_move_to_next(page_cur_t *cur)
{
return cur->rec= page_rec_get_next(cur->rec);
}
MY_ATTRIBUTE((nonnull, warn_unused_result))
inline rec_t *page_cur_move_to_prev(page_cur_t *cur)
{
return cur->rec= page_rec_get_prev(cur->rec);
}
#include "page0cur.inl"
#endif